The overall objective of this proposal is to define chemical properties of synthetic polymers which affect the local response of tissue to implanted materials. General chemical properties such as charge, hydrophobicity and hydrophilicity, as well as the specific chemical type, presumably affect the foreign body reaction to implanted material, but there is at present a large gap in fundamental knowledge in this area. A systematic examination of the cellular response to a chemically well characterized series of materials is proposed in order to provide a better understanding of tissue-material interactions. The differential response of living tissue to implanted foreign materials in vivo may be related to differences in initial reactions of certain cell types with these materials in vitro. This proposal therefore consists of an examination of tissue-material interactions both in vitro and in vivo, organized as follows: (1) Identification of chemical properties of synthetic materials which affect adhesion of neutrophils, fibroblasts, and macrophages, or affect neutrophil lysosomal release, in vitro. (2) Characterization of the foreign body reaction to a series of materials of widely divergent adhesive properties for these cell types. (3) Examination of the effect of protein adsorbed on materials on the response of cells to the material, both in vitro and in vivo.